(1) After determining an amount of the ZLEV charge payable by the registered operator of a ZLEV, the Secretary must issue an invoice to the registered operator for payment of the amount.
(2) An invoice must—
(a) state the amount of the ZLEV charge to which the invoice relates; and
(b) state the date by which the amount must be paid, which must be at least 14 days after the date the invoice is issued; and
(c) set out how the amount was calculated; and
(d) state any interest payable by the registered operator in respect of previous unpaid invoices.